The global energy challenge is universal, and a transfer to alternative sustainable energy sources, in particular the sun, is inevitable. One requirement for current energy consumption is that the energy be available not only during sunlight hours, but also during the evening and night when the sunlight is not available. Thus, methods for storing energy in both electrical and chemical forms are desirable. Efforts are being made to store hydrogen as a source of energy. An ideal process for hydrogen production is to use water as a hydrogen source together with solar energy for conversion. Accordingly, photocatalytic water splitting (which is the light-induced conversion reaction of water to hydrogen and oxygen) has attracted attention as one of the most promising hydrogen production processes.
Efficient water splitting, using photocatalysts, has been a huge challenge for researchers. Moreover, water splitting by using a renewable form of energy is possibly the ultimate solution to environmental and energy issues. Nevertheless, the development of inexpensive, readily available and highly active photocatalysts for water splitting has limited development.